Water and sanitation innovations for non-grid solutions – an inter- and transdisciplinary strategic research program

Wings strives to develop novel non-grid water and sanitation systems that can function as comparable alternatives to network-based systems. We do this by:

  • Studying such systems from a variety of different perspectives (engineering, decision analysis, development studies, transition and innovation studies, and behavioral studies)
  • Working in close collaboration with key stakeholders from different sectors and decision levels
  • Pursuing research in different socio-economic contexts (research pillars), ranging from industrialized countries to emerging and developing countries
  • Addressing conceptual and methodological issues that link and relate existing research projects in different contexts (transversal projects)
  • Building on current and past research projects in the field of urban water management


The management of urban water systems has been a core responsibility of civil society throughout history. This reflects the central importance of these systems for human welfare and environmental protection. The current conventional approach to urban water management builds on well-established socio-technical systems that have evolved over the last century and have solved most of the water- and hygiene-related problems afflicting OECD countries in the past. These predominantly centralized and networked systems reliably treat and provide drinking water and safely transport, treat, and dispose wastewater. Challenges are posed, however, by population growth (both increases and decreases), climate change, emerging contaminants, as well as by the need to rehabilitate and replace aging infrastructure.

Though there is still an ongoing debate whether there is a need for new approaches in OECD countries, leading research institutes, international organizations and national governments are increasingly acknowledging that the conventional approach to urban water management cannot be the only solution for rapidly expanding cities in low- and middle-income countries in Africa, Asia and Latin America. With centralized and networked urban water systems out of reach for a large part of the global urban population, there is an urgent need for developing fundamentally new approaches, i.e. more flexible, cost-effective, resource-efficient non-grid systems that are able to cope with current and future urban water challenges.


Program management

Dr. Sabine Hoffmann Group Leader, Cluster: ITD Tel. +41 58 765 6818 Send Mail
Lisa Deutsch Doctoral Student, Cluster: ITD Tel. +41 58 765 5326 Send Mail

Program team


Dr. Christoph Lüthi Dr. Eng. Infrastructure Planning Tel. +41 58 765 5614 Send Mail


Prof. Dr. Bernhard Truffer Department head, Cluster Cirus Tel. +41 58 765 5670 Send Mail
Dr. Christian Binz Group Leader, Cluster: Cirus Tel. +41 58 765 5030 Send Mail
Dr. Nadja Contzen Group leader, Environmental Health Psychology Tel. +41 58 765 6892 Send Mail
Dr. Sabine Hoffmann Group Leader, Cluster: ITD Tel. +41 58 765 6818 Send Mail
Lisa Deutsch Doctoral Student, Cluster: ITD Tel. +41 58 765 5326 Send Mail

Research pillars and projects

We organize our research within four research pillars. Each pillar covers a typical socio-technical system configuration. The program builds on current and past research activities in the involved departments of Eawag and aims to add value to these projects.

Wings Disconnect

Wings Disconnect identifies the conditions for decentralized water systems in contexts with well-established governance structures, medium to high incomes and high degrees of centralization. Compared with the dominating approach of water supply and sewer networks, decentralized systems promise to respond more favorably to new requirements such as rapid demographic variation, climate change or other planning uncertainties. Additionally, there is a growing unease that it might not be financially sustainable to continue to maintain the existing aging pipe networks.

Wings Disconnect provides the scientific base for identifying whether system change towards non-grid-connected water and sanitation solutions could alleviate these concerns and improve the financial sustainability of urban water infrastructures. To do this, we elaborate where and when it is possible to disconnect from the centralized system and implement non-grid-connected systems (particularly small treatment plants) and identify potential infrastructure transition paths. This includes developing methods to determine the optimal degree of infrastructural centralization, quantify the performance of entire systems, identify industrial opportunities, and support decision-making over time.

Current Projects

We are identifying the challenges of modular infrastructure systems for the Swiss economy and society using the example of urban water management.
Project aim is participative decision support for the long-term transition to innovative wastewater infrastructures.
Decentralisation changes wastewater quantity and quality that is discharged to the sewer. We investigate the effects of these changes on the operation of existing centralised sewer systems.

Past Projects

How can the overall performance of distributed treatment systems be estimated and maintained?
The aim of this project is to gain more insight about sustainable infrastructure management and to develop tools and methods for complex decision making for infrastructure planning.

Wings Hybrid

Wings Hybrid investigates new models and methods to recycle nutrients, water and energy in future cities, particularly within the context of climate change. Conventionally, mixed wastewater is separated and treated in centralized wastewater treatment plants. We aim to establish viable alternatives for full-scale applications that collect and treat the wastewater flows separately according to the type and concentration of their contaminants. By doing so, water, nutrients and energy can easily be recovered, thus increasing water and energy productivity.

Wings Hybrid develops further urine separation and treatment to reuse anthropogenic nutrients in agriculture, as well as greywater treatment, to regenerate water with high chemical and microbial quality. This includes technical development and optimization through practical trials in a living lab, implementation of demonstration projects and collaboration with industrial partners.

Current Projects

We develop reactors for the separate treatment of urine, feces and water directly in the toilet.
NEST building
Sustainable urban water and wastewater management applied and implemented in the modular NEST building.
Serious games and gamification are increasingly used to engage stakeholders. We study whether and how they make decision analysis more participatory.

Past Projects

By recovering nutrients from urine, we develop a sanitation system, which produces a valuable fertiliser

Wings Emerging

Wings Emerging explores innovation in emerging markets characterized by rapid urbanization, an expanding middle-income population and overall economic growth, leading to rising living standards, increasing construction activities and growing resource demands (water, energy, services, etc.). Because of these particular characteristics, we assume that new urban development areas in emerging markets are among the most promising potential lead-markets for innovative non-grid-connected solutions that encompass water supply, wastewater treatment, waste disposal and energy supply in a holistic way.

Wings Emerging aims to inspire and support decision makers and niche players on how to transition towards such holistic solutions that allow for meeting growing demands while recovering resources. This includes analyzing the relevant capabilities necessary to succeed with such innovations, studying innovation paths to introduce non-grid-connected solutions and exploring barriers and drivers for their diffusion.

Current Projects

RADEC seeks to unravel how emerging countries can simultaneously achieve industrial leapfrogging and environmental sustainability transition by analyzing the industrial and socio-technical aspects of decentralized water and sanitation systems in China, India and South Africa.
4S is assessing small-scale sanitation systems in South Asia to provide policy recommendations for improved sanitation system design, implementation and O&M.

Wings Informal

Wings Informal analyzes non-grid solutions for some of the most intractable, complex and rapidly expanding built environments in the developing world: informal settlements. Residents of these areas are disadvantaged as they lack formal access to land, housing and basic urban services. Solutions will therefore have to build on sound technological approaches, while also meeting the specific needs and specific resource constraints that are found in this context.

Understanding the broader complexities of current, heterogeneous sanitation systems with particular focus on the interfaces between these systems is the aim of Wings Informal. This includes analyzing the enabling environments that support or hinder the successful introduction of these solutions, exploring the scaling conditions for business models with particular focus on container-based systems, and identifying the challenges and opportunities related to scaling innovations in informal settlements.

Current Projects

The aim of CWIS research is to develop a method that synthesizes existing information about the sanitation landscapes of cities in India and that presents comprehensive sanitation solutions.
We seek to understand how formal and informal institutions, planning procedures and resources drive or constrain informal settlements upgrading in Sub Saharan Africa cities.

Past Projects

Development of systematic but generic methods for the generation of locally appropriate sanitation system options and for the quantification of sustainability performance indicators.
The proposal analyzes possible transition pathways in basic services, focusing specifically on the case of Nairobi, Kenya.
In this project, we work with organizations from around the globe to identify factors for managing water kiosks sucessfully
In this project, we collaborate with various organizations to study the role of business innovation in the scaling process of sanitation services.
In this project, we apply Business Model Thinking to create promising business models around innovative water and sanitation technologies

Wings Transversal

Transversal projects projects bundle conceptual and methodological needs of the pillars and/or the overall program. By doing so, they strengthen the connection within the interdisciplinary research team.

Current Projects

The INTEGRATE project aims at strengthening inter- and transdisciplinary integration within and across the strategic research program Wings.
The BARRIERS project aims at improving our understanding of the institutional barriers for radical innovation in UWM. It analyzes ‘lighthouse cities’ that experiment with non-grid UWM systems
Perceived distributive justice and acceptance of decentralised water and wastewater systems
The Lighthouse Project focuses on visible examples of onsite and decentralised urban water management systems, which will play a key role in enabling sustainability transitions.


Urban Water Management

Heiberg, J.; Truffer, B.; Binz, C. (2022) Assessing transitions through socio-technical configuration analysis – a methodological framework and a case study in the water sector, Research Policy, 51(1), 104363 (19 pp.), doi:10.1016/j.respol.2021.104363, Institutional Repository
Duque, N.; Bach, P. M.; Scholten, L.; Fappiano, F.; Maurer, M. (2022) A simplified sanitary sewer system generator for exploratory modelling at city-scale, Water Research, 209, 117903 (12 pp.), doi:10.1016/j.watres.2021.117903, Institutional Repository
Heiberg, J.; Truffer, B. (2022) Overcoming the harmony fallacy: how values shape the course of innovation systems, Environmental Innovation and Societal Transitions, 42, 411-428, doi:10.1016/j.eist.2022.01.012, Institutional Repository
Larsen, T. A.; Riechmann, M. E.; Udert, K. M. (2021) State of the art of urine treatment technologies: a critical review., Water Research X, 13, 100114 (20 pp.), doi:10.1016/j.wroa.2021.100114, Institutional Repository
Hacker, M. E.; Binz, C. (2021) Institutional barriers to on-site alternative water systems: a conceptual framework and systematic analysis of the literature, Environmental Science and Technology, 55(12), 8267-8277, doi:10.1021/acs.est.0c07947, Institutional Repository
Larsen, T. A.; Gruendl, H.; Binz, C. (2021) The potential contribution of urine source separation to the SDG agenda - a review of the progress so far and future development options, Environmental Science: Water Research and Technology, 7(7), 1161-1176, doi:10.1039/D0EW01064B, Institutional Repository
Reynaert, E.; Hess, A.; Morgenroth, E. (2021) Making waves: why water reuse frameworks need to co-evolve with emerging small-scale technologies, Water Research X, 11, 100094 (5 pp.), doi:10.1016/j.wroa.2021.100094, Institutional Repository
Spuhler, D.; Scheidegger, A.; Maurer, M. (2021) Ex-ante quantification of nutrient, total solids, and water flows in sanitation systems, Journal of Environmental Management, 280, 111785 (17 pp.), doi:10.1016/j.jenvman.2020.111785, Institutional Repository
Hess, A.; Bettex, C.; Morgenroth, E. (2020) Influence of intermittent flow on removal of organics in a biological activated carbon filter (BAC) used as post-treatment for greywater, Water Research X, 9, 100078 (10 pp.), doi:10.1016/j.wroa.2020.100078, Institutional Repository
Hoffmann, S.; Feldmann, U.; Bach, P. M.; Binz, C.; Farrelly, M.; Frantzeskaki, N.; Hiessl, H.; Inauen, J.; Larsen, T. A.; Lienert, J.; Londong, J.; Lüthi, C.; Maurer, M.; Mitchell, C.; Morgenroth, E.; Nelson, K. L.; Scholten, L.; Truffer, B.; Udert, K. M. (2020) A research agenda for the future of urban water management: exploring the potential of non-grid, small-grid, and hybrid solutions, Environmental Science and Technology, 54(9), 5312-5322, doi:10.1021/acs.est.9b05222, Institutional Repository
Larsen, T. A. (2020) Urine source separation for global nutrient management, In: O’Bannon, D. J. (Eds.), Women in water quality. Investigations by prominent female engineers, 99-111, doi:10.1007/978-3-030-17819-2_6, Institutional Repository
Pakizer, K.; Fischer, M.; Lieberherr, E. (2020) Policy instrument mixes for operating modular technology within hybrid water systems, Environmental Science and Policy, 105, 120-133, doi:10.1016/j.envsci.2019.12.009, Institutional Repository
Gründl, H.; Larsen, T. A. (2019) The toilet revolution: improved water pollution control and reuse of wastewater in urban slums and in modern cities, World Architecture, 36-39, Institutional Repository
Maurer, M.; Hoffmann, S. (2019) Sanierungsfall Abwassersystem, Volkswirtschaft, 89(6), 12-15, Institutional Repository
Schneider, M. Y.; Carbajal, J. P.; Furrer, V.; Sterkele, B.; Maurer, M.; Villez, K. (2019) Beyond signal quality: the value of unmaintained pH, dissolved oxygen, and oxidation-reduction potential sensors for remote performance monitoring of on-site sequencing batch reactors, Water Research, 161, 639-651, doi:10.1016/j.watres.2019.06.007, Institutional Repository
Thürlimann, C. M.; Udert, K. M.; Morgenroth, E.; Villez, K. (2019) Stabilizing control of a urine nitrification process in the presence of sensor drift, Water Research, 165, 114958 (10 pp.), doi:10.1016/j.watres.2019.114958, Institutional Repository
Aubert, A. H.; Bauer, R.; Lienert, J. (2018) A review of water-related serious games to specify use in environmental Multi-Criteria Decision Analysis, Environmental Modelling and Software, 105, 64-78, doi:10.1016/j.envsoft.2018.03.023, Institutional Repository
Reymond, P.; Renggli, S.; Lüthi, C. (2016) Towards sustainable sanitation in an urbanising world, In: Ergen, M. (Eds.), Sustainable urbanisation, 116-134, doi:10.5772/63726, Institutional Repository
Larsen, T. A.; Hoffmann, S.; Lüthi, C.; Truffer, B.; Maurer, M. (2016) Emerging solutions to the water challenges of an urbanizing world, Science, 352(6288), 928-933, doi:10.1126/science.aad8641, Institutional Repository
Eggimann, S.; Truffer, B.; Maurer, M. (2015) To connect or not to connect? Modelling the optimal degree of centralisation for wastewater infrastructures, Water Research, 84, 218-231, doi:10.1016/j.watres.2015.07.004, Institutional Repository

Inter- and Transdisciplinarity

Deutsch, L.; Belcher, B.; Claus, R.; Hoffmann, S. (2021) Leading inter- and transdisciplinary research: lessons from applying theories of change to a strategic research program, Environmental Science and Policy, 120, 29-41, doi:10.1016/j.envsci.2021.02.009, Institutional Repository
Pohl, C.; Fam, D.; Hoffmann, S.; Mitchell, C. (2019) Exploring Julie Thompson Klein's framework for analysis of boundary work, Issues in Interdisciplinary Studies, 37(2), 62-89, Institutional Repository
Hoffmann, S.; Thompson Klein, J.; Pohl, C. (2019) Linking transdisciplinary research projects with science and practice at large: introducing insights from knowledge utilization, Environmental Science and Policy, 102, 36-42, doi:10.1016/j.envsci.2019.08.011, Institutional Repository
Hitziger, M.; Aragrande, M.; Berezowski, J. A.; Canali, M.; Del Rio Vilas, V.; Hoffmann, S.; Igrejas, G.; Keune, H.; Lux, A.; Bruce, M.; Palenberg, M. A.; Pohl, C.; Radeski, M.; Richter, I.; Robledo Abad, C.; Salerno, R. H.; Savic, S.; Schirmer, J.; Vogler, B. R.; Rüegg, S. R. (2019) EVOLvINC: evaluating knowledge integration capacity in multistakeholder governance, Ecology and Society, 24(2), 36 (16 pp.), doi:10.5751/ES-10935-240236, Institutional Repository
Maag, S.; Alexander, T. J.; Kase, R.; Hoffmann, S. (2018) Indicators for measuring the contributions of individual knowledge brokers, Environmental Science and Policy, 89, 1-9, doi:10.1016/j.envsci.2018.06.002, Institutional Repository

Case Studies

Beutler, P.; Larsen, T. A.; Maurer, M.; Staufer, P.; Lienert, J. (2021) Potenzial dezentraler Abwassersysteme, Aqua & Gas, 101(1), 66-75, Institutional Repository
Hacker, M. E.; Binz, C. (2021) Navigating institutional complexity in socio-technical transitions, Environmental Innovation and Societal Transitions, 40, 367-381, doi:10.1016/j.eist.2021.09.003, Institutional Repository
Ulrich, L.; Reymond, P.; Chandragiri, R.; Lüthi, C. (2021) Governance of small-scale sanitation in India. Institutional analysis and policy recommendations. Small‐scale sanitation scaling‐up (4S) - project report vol. II, 162 p, Institutional Repository
Sutherland, C.; Reynaert, E.; Sindall, R. C.; Riechmann, M. E.; Magwaza, F.; Lienert, J.; Buthelezi, S.; Khumalo, D.; Dhlamini, S.; Morgenroth, E.; Udert, K. M. (2021) Innovation for improved hand hygiene: field testing the Autarky handwashing station in collaboration with informal settlement residents in Durban, South Africa, Science of the Total Environment, 796, 149024 (13 pp.), doi:10.1016/j.scitotenv.2021.149024, Institutional Repository
Sutherland, C.; Reynaert, E.; Dhlamini, S.; Magwaza, F.; Lienert, J.; Riechmann, M. E.; Buthelezi, S.; Khumalo, D.; Morgenroth, E.; Udert, K. M.; Sindall, R. C. (2021) Socio-technical analysis of a sanitation innovation in a peri-urban household in Durban, South Africa, Science of the Total Environment, 755, 143284 (12 pp.), doi:10.1016/j.scitotenv.2020.143284, Institutional Repository
Doll, C.; Larsen, T. A.; Strande, L.; Udert, K. M.; Morgenroth, E. (2020) Water Hub im NEST-Gebäude. Eine Plattform zum Testen von innovativen ressourcenorientierten Sanitärsystemen, Aqua & Gas, 100(2), 52-57, Institutional Repository
Narayan, A. S.; Fischer, M.; Lüthi, C. (2020) Social network analysis for water, sanitation, and hygiene (WASH): application in governance of decentralized wastewater treatment in India using a novel validation methodology, Frontiers in Environmental Science, 7, 198 (18 pp.), doi:10.3389/fenvs.2019.00198, Institutional Repository
Reymond, P.; Chandragiri, R.; Ulrich, L. (2020) Governance arrangements for the scaling up of small-scale wastewater treatment and reuse systems - lessons from India, Frontiers in Environmental Science, 8, 72 (16 pp.), doi:10.3389/fenvs.2020.00072, Institutional Repository
Reynaert, E.; Greenwood, E. E.; Ndwandwe, B.; Riechmann, M. E.; Sindall, R. C.; Udert, K. M.; Morgenroth, E. (2020) Practical implementation of true on-site water recycling systems for hand washing and toilet flushing, Water Research X, 7, 100051 (13 pp.), doi:10.1016/j.wroa.2020.100051, Institutional Repository
Beutler, P.; Lienert, J. (2020) Zukünftige Abwasserentsorgung im ländlichen Raum - Fallstudie 1. Technischer Bericht zur Entscheidungsunterstützung für die Gemeinde, 247 p, Institutional Repository
Cherunya, P. C.; Ahlborg, H.; Truffer, B. (2020) Anchoring innovations in oscillating domestic spaces: why sanitation service offerings fail in informal settlements, Research Policy, 49(1), 103841 (16 pp.), doi:10.1016/j.respol.2019.103841, Institutional Repository
van Welie, M. J.; Truffer, B.; Yap, X.-S. (2019) Towards sustainable urban basic services in low-income countries: a Technological Innovation System analysis of sanitation value chains in Nairobi, Environmental Innovation and Societal Transitions, 33, 196-214, doi:10.1016/j.eist.2019.06.002, Institutional Repository
Yap, X.-S.; Truffer, B. (2019) Shaping selection environments for industrial catch-up and sustainability transitions: a systemic perspective on endogenizing windows of opportunity, Research Policy, 48, 1030-1047, doi:10.1016/j.respol.2018.10.002, Institutional Repository
Eggimann, S.; Truffer, B.; Feldmann, U.; Maurer, M. (2018) Screening European market potentials for small modular wastewater treatment systems – an inroad to sustainability transitions in urban water management?, Land Use Policy, 78, 711-725, doi:10.1016/j.landusepol.2018.07.031, Institutional Repository
van Welie, M. J.; Cherunya, P. C.; Truffer, B.; Murphy, J. T. (2018) Analysing transition pathways in developing cities: the case of Nairobi's splintered sanitation regime, Technological Forecasting and Social Change, 137, 259-271, doi:10.1016/j.techfore.2018.07.059, Institutional Repository
Binz, C.; Truffer, B.; Coenen, L. (2016) Path creation as a process of resource alignment and anchoring: industry formation for on-site water recycling in Beijing, Economic Geography, 92(2), 172-200, doi:10.1080/00130095.2015.1103177, Institutional Repository


Dr. Sabine Hoffmann Group Leader, Cluster: ITD Tel. +41 58 765 6818 Send Mail
Lisa Deutsch Doctoral Student, Cluster: ITD Tel. +41 58 765 5326 Send Mail

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      What do sustainable neighborhood planning, a urine fertilizer and a traditional Swiss Apéro have in common? The answer can be found in our new short film "Verhebets? A Resource-Oriented Apéro" about the potentials of a resource-oriented urban water management. The Global Science Film Festival has also now nominated the short film in the category "Best Short Film 2023".

      The Wings Team published an inter- and transdisciplinary research agenda on the future of urban water management together with a group of international researchers.


      Program Structure